Sample Tube And Device And Method For Dispersion And Homogenization

Abstract

A sample tube includes a cylindrical wall and a first end and a second end. The first end of the sample tube is closed by a base, such that a sample-receiving space with a longitudinal axis is formed between base and cylindrical wall. The second end has a closure piece connected releasably thereto. A weight element is received inside the receiving space and is shaped and dimensioned in such a way that the weight element can rotate freely in the receiving space only about the longitudinal axis of the latter. The application further relates to a method and a device with which a sample located in the sample tube can be dispersed or homogenized by rotational movement of the sample tube.

Claims

1. A sample tube, comprising: a cylindrical wall and a first end and a second end, the first end being closed by a base, such that a sample-receiving space with a longitudinal axis is formed between the base and a cylindrical wall, the second end having a closure piece connected releasably thereto, wherein a weight element is received inside the receiving space said weight element being shaped and dimensioned in such a way that the weight element can rotate freely in the receiving space only about the longitudinal axis of the latter.

2. The sample tube according to claim 1, wherein the closure piece has a first friction surface on a face which is directed toward the receiving space when the closure piece is connected to the second end.

3. The sample tube according to claim 1, wherein the weight element is in the form a cylinder that has a cross section smaller than the cross section of the receiving space.

4. The sample tube according to claim 1, wherein the weight element has a second friction surface on at least one face which is directed toward the first or second end.

5. The sample tube according to claim 2, wherein the first friction surface has structural elements, in particular teeth, pyramids or grooves.

6. The sample tube according to one of claim 1, wherein the weight element is made of glass, stainless steel, ceramic or a polymer.

7. A device for the dispersion or homogenization of a sample, comprising a housing with at least one receptacle for a sample tube according to claim 6, which receptacle is able to be moved in particular in an oscillating or intermittent rotational movement, by a drive of the device.

8. The device according to claim 7, wherein the rotational movement is centric.

9. Kit of parts comprising a device according to claim 7 and of at least one sample tube according to claim 1.

10. A method for the dispersion or homogenization of a sample, comprising the steps of: a) providing a sample tube according to claim 1; b) introducing the sample into the receiving space, such that the sample is located between weight element and first or second end; c) connecting the closure piece to the second end; d) turning the sample tube in such a way that the sample is located below the weight element in the direction of gravity; and e) setting the sample tube in a rotational movement about a longitudinal axis of the receiving space.

11. The method according to claim 10, wherein the rotation of the sample tube is an oscillating rotational movement.

12. The method according to claim 10, wherein the rotation of the sample tube is performed intermittently.

13. The sample tube according to claim 4, wherein the second friction surface has structural elements, in particular teeth, pyramids or grooves.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In the drawings used to explain the illustrative embodiment:

[0053] FIG. 1 shows an embodiment of a sample tube according to the disclosure;

[0054] FIG. 2 shows a bottom view of the closure piece of the sample tube from FIG. 1;

[0055] FIG. 3 shows a schematic view of a device according to the disclosure for dispersion and homogenization.

[0056] In the figures, in principle, like parts are provided with like reference signs.

DETAILED DESCRIPTION

[0057] FIG. 1 shows an embodiment of a sample tube 1 according to the disclosure. The sample tube 1 has a cylindrical wall 2. A first end of the sample tube 1 is closed with a base 3. The cylindrical wall 2 and the base 3 define a receiving space 4 in which a sample can be received. At a second end, which lies opposite the first end, the sample tube has a closure piece 5 which, in the illustrative embodiment shown, is a screw-on lid. A weight element 7 is received inside the receiving space 4. The weight element 7 has a shape and size that allow it a rotation about the longitudinal axis A of the receiving space 4, but basically no further rotations about further axes. In the embodiment shown, the weight element 7 has a cylindrical shape. A movement of the weight element 7 along the longitudinal axis A of the receiving space 4 and slight movements along axes orthogonal to the longitudinal axis A are likewise possible. In the receiving space 4, the sample tube has a sterile liquid 18, which is located between the weight element 7 and the second end of the sample tube.

[0058] FIG. 1 shows the sample tube in a state in which it is standing vertically with its base 3 on a surface, that is to say the longitudinal axis A is parallel to the direction of gravity. Therefore, the weight element 7 correspondingly lies on the base 3. The weight element 7 has a second friction surface 8 on one of its end faces.

[0059] FIG. 2 shows a bottom view of the closure piece 5 in the form of the screw-on lid from FIG. 1. As will be seen, the closure piece 5 has a first friction surface 6 on its side pointing toward the receiving space 4 in the closed state. Both the first friction surface 6 of the closure piece and the second friction surface 8 of the weight element 7 have structural elements that increase the roughness of the first and second friction surfaces 6, 8.

[0060] FIG. 3 shows a schematic view of a device 10 according to the disclosure for the dispersion or homogenization of a sample in combination with the sample tube 1 according to FIG. 1 and FIG. 2.

[0061] The device 10 has a housing 11 on which a receptacle 12 for the sample tube 1 is arranged. The receptacle 12 is designed in such a way that the closure piece 5 of the sample tube is partially inserted therein and is connected to it by form-fit engagement. The receptacle 12 is set in a rotational movement by a drive 13 of the device 10, which drive 13 is located in the housing 11 and is therefore only symbolized by dashed lines. By the rotational movement of the receptacle 12, the sample tube 1 connected to the latter is likewise set in the same rotational movement about the longitudinal axis A of the receiving space.

[0062] A sample 9 is received in the receiving space 4. In the embodiment shown, the sample 9 is a solid sample located in the liquid 18 of the sample tube 1. After the sample 9 has been introduced into the receiving space, the sample tube 1 is turned so that it can be fastened to the receptacle 12. As this is being done, the sample 9 slips or flows by gravity to that side of the closure piece 5 directed toward the receiving space 4. The weight element 7 in the receiving space will also slip by gravity along the longitudinal axis A in the direction of the closure piece. In this way, the sample 9 is enclosed between closure piece 5 and weight element 7.

[0063] The sample 9 is likewise set in rotational movement on account of the friction with the closure piece 5 and the cylindrical wall 2; however, on account of the inertia, this happens with a time delay relative to the rotational movement of the sample tube 1. On account of the friction between the sample 9 and the weight element 7, the weight element 7 is finally also set in rotational movement, but with a time delay relative to the sample 9. As a result of this time delay, the rotational movement of the sample tube 1, of the sample 9 and of the weight element 7 takes place at different speeds. This results in force being introduced into the sample, in particular in the form of shear forces. After some time, the rotational speeds equalize. Therefore, the device 10 has a control 14 (indicated by dashed lines) which is arranged inside the housing 11 and which controls the drive 13 of the receptacle 12 in such a way that the rotational movement is intermittent or oscillating. That is to say, there is a periodic change in the speed or in the direction of rotation. Thus, a difference in speed between the rotational movements of the sample tube 1, the sample 9 and the weight element 7 can be maintained in a substantially permanent manner.

[0064] The device 1 moreover has a display 15, on which parameters of the rotational movement of the receptacle can be displayed for example, and a key serving as input means 16, with which a user can initiate the start of the rotational movement. The device 1 further comprises a cover 17 which encloses the at least one receptacle 12.